Intelligent transportation system wikipedia, the free encyclopedia

6/24/12 Intelligent transportation system - Wikipedia, the free encyclopedia

Intelligent transportation system
From Wikipedia, the free encyclopedia

Intelligent Transport Systems (ITS) are advanced appli cations which, without embodying intelligence as such, aim
to provide innovative services relating to different modes of transport and traffic management and enable various
users to be better informed and make safer, more coordinated, and ‘smarter’ use of transport networks.

Although ITS may refer to all modes of transport, EU Directive 2010/40/EU of 7 July 2010 on the framework for
the deployment of Intelligent Transport Systems in the field of road transport and for interfaces with other modes of
transport defines ITS as systems in which information and communication technologies are applied in the field of
road transport, including infra
structure, vehicles and users, and in traffic management and mobility management, as
well as for interfaces with other modes of transport.[1] (http://eur-lex.europa.eu/LexUriServ/LexUriServ.do?
uri=OJ:L:2010:207:0001:0013:EN:PDF)

Contents
1 Background
2 Intelligent transport technologies
2.1 Wireless communications
2.2 Computational technologies
2.3 Floating car data/floating cellular data
2.4 Sensing technologies
2.5 Inductive loop detection
2.6 Video vehicle detection
2.7 Bluetooth Detection
3 Intelligent transport applications
3.1 Emergency vehicle notification systems
3.2 Automatic road enforcement
3.3 Variable speed limits
3.4 Collision avoidance systems
3.5 Dynamic Traffic Light Sequence
4 Cooperative systems on the road
5 ITS World Congress
6 United States
7 See also
8 References
9 External links

Background
Interest in ITS comes from the problems caused by traffic congestion and a synergy of new information technology
for simulation, real-time control, and communications networks. Traffic congestion has been increasing worldwide
as a result of increased motorization, urbanization, population growth, and changes in population density.
en.wikipedia.org/wiki/Intelligent_transportation_system 1/8


Congestion reduces efficiency of transportation infrastructure and increases travel time, air pollution, and fuel
consumption.

The United States, for example, saw large increases in both motorization and urbanization starting in the 1920s that
led to migration of the population from the sparsely populated rural areas and the densely packed urban areas into
suburbs. The industrial economy replaced the agricultural economy, leading the population to move from rural
locations into urban centers. At the same time, motorization was causing cities to expand because motorized
transportation could not support the population density that the existing mass transit systems could. Suburbs
provided a reasonable compromise between population density and access to a wide variety of employment,
goods, and services that were available in the more densely populated urban centers. Further, suburban
infrastructure could be built quickly, supporting a rapid transition from a rural/agricultural economy to an
industrial/urban economy.[citation needed]

Recent governmental activity in the area of ITS – specifically in the United States – is further motivated by an
increasing focus on homeland security. Many of the proposed ITS systems also involve surveillance of the
roadways, which is a priority of homeland security.[1] Funding of many systems comes either directly through
homeland security organizations or with their approval. Further, ITS can play a role in the rapid mass evacuation of
people in urban centers after large casualty events such as a result of a natural disaster or threat. Much of the
infrastructure and planning involved with ITS parallels the need for homeland security systems.

In the developing world, the migration of people from rural to urbanized habitats has progressed differently. Many
areas of the developing world have urbanized without significant motorization and the formation of suburbs. In areas
like Santiago, Chile, a high population density is supported by a multimodal system of walking, bicycle
transportation, motorcycles, buses, and trains. A small portion of the population can afford automobiles, but the
automobiles greatly increase the congestion in these multimodal transportation systems. They also produce a
considerable amount of air pollution, pose a significant safety risk, and exacerbate feelings of inequities in the
society.

Other parts of the developing world, such as China, remain largely rural but are rapidly urbanizing and
industrializing. In these areas a motorized infrastructure is being developed alongside motorization of the population.
Great disparity of wealth means that only a fraction of the population can motorize, and therefore the highly dense
multimodal transportation system for the poor is cross-cut by the highly motorized transportation system for the
rich. The urban infrastructure is being rapidly developed, providing an opportunity to build new systems that
incorporate ITS at early stages.

Intelligent transport technologies
Intelligent transport systems vary in technologies applied, from basic management systems such as car navigation;
traffic signal control systems; container management systems; variable message signs; automatic number plate
recognition or speed cameras to monitor applications, such as security CCTV systems; and to more advanced
applications that integrate live data and feedback from a number of other sources, such as parking guidance and
information systems; weather information; bridge deicing systems; and the like. Additionally, predictive techniques
are being developed to allow advanced modeling and comparison with historical baseline data. Some of these
technologies are described in the following sections.

Wireless communications

Various forms of wireless communications technologies have been proposed for intelligent transportation systems.


Radio modem communication on UHF and VHF frequencies are widely used for short and long range
communication within ITS.

Short-range communications (less than 500 yards) can be accomplished using IEEE 802.11 protocols, specifically
WAVE or the Dedicated Short Range Communications standard being promoted by the Intelligent Transportation
Society of America and the United States Department of Transportation. Theoretically, the range of these protocols
can be extended using Mobile ad-hoc networks or Mesh networking.

Longer range communications have been proposed using infrastructure networks such as WiMAX (IEEE 802.16),
Global System for Mobile Communications (GSM), or 3G. Long-range communications using these methods are
well established, but, unlike the short-range protocols, these methods require extensive and very expensive
infrastructure deployment. There is lack of consensus as to what business model should support this infrastructure.

Computational technologies

Recent advances in vehicle electronics have led to a move toward fewer, more capable computer processors on a
vehicle. A typical vehicle in the early 2000s would have between 20 and 100 individual networked
microcontroller/Programmable logic controller modules with non-real-time operating systems. The current trend is
toward fewer, more costly microprocessor modules with hardware memory management and Real-Time Operating
Systems. The new embedded system platforms allow for more sophisticated software applications to be
implemented, including model-based process control, artificial intelligence, and ubiquitous computing. Perhaps the
most important of these for Intelligent Transportation Systems is artificial intelligence.[citation needed]

Floating car data/floating cellular data

Main article: Floating car data

"Floating car" or "probe" data collection is a set of relatively low-cost methods for obtaining travel time and speed
data for vehicles traveling along streets, highways, freeways, and other transportation routes. Broadly speaking,
three methods have been used to obtain the raw data:

Triangulation Method. In developed countries a high proportion of cars contain one or more mobile
phones. The phones periodically transmit their presence information to the mobile phone network, even when
no voice connection is established. In the mid 2000s, attempts were made to use mobile phones as
anonymous traffic probes. As a car moves, so does the signal of any mobile phones that are inside the
vehicle. By measuring and analyzing network data using triangulation, pattern matching or cell-sector statistics
(in an anonymous format), the data was converted into traffic flow information. With more congestion, there
are more cars, more phones, and thus, more probes. In metropolitan areas, the distance between antennas is
shorter and in theory accuracy increases. An advantage of this method is that no infrastructure needs to be
built along the road; only the mobile phone network is leveraged. But in practice the triangulation method can
be complicated, especially in areas where the same mobile phone towers serve two or more parallel routes
(such as a freeway with a frontage road, a freeway and a commuter rail line, two or more parallel streets, or
a street that is also a bus line). By the early 2010s, the popularity of the triangulation method was declining.
Vehicle Re-Identification. Vehicle re-identification methods require sets of detectors mounted along the
road. In this technique, a unique serial number for a device in the vehicle is detected at one location and then
detected again (re-identified) further down the road. Travel times and speed are calculated by comparing the
time at which a specific device is detected by pairs of sensors. This can be done using the MAC (Machine


Access Control) addresses from Bluetooth devices,[2] or using the RFID serial numbers from Electronic Toll
Collection (ETC) transponders (also called "toll tags").
GPS Based Methods. An increasing number of vehicles are equipped with in-vehicle GPS (satellite
navigation) systems that have two-way communication with a traffic data provider. Position readings from
these vehicles are used to compute vehicle speeds.

Floating car data technology provides advantages over other methods of traffic measurement:

Less expensive than sensors or cameras
More coverage (potentially including all locations and streets)
Faster to set up and less maintenance
Works in all weather conditions, including heavy rain

Sensing technologies

Technological advances in telecommunications and information technology, coupled with state-of-the-art microchip,
RFID (Radio Frequency Identification), and inexpensive intelligent beacon sensing technologies, have enhanced the
technical capabilities that will facilitate motorist safety benefits for intelligent transportation systems globally. Sensing
systems for ITS are vehicle- and infrastructure-based networked systems, i.e., Intelligent vehicle technologies.
Infrastructure sensors are indestructible (such as in-road reflectors) devices that are installed or embedded in the
road or surrounding the road (e.g., on buildings, posts, and signs), as required, and may be manually disseminated
during preventive road construction maintenance or by sensor injection machinery for rapid deployment. Vehicle-
sensing systems include deployment of infrastructure-to-vehicle and vehicle-to-infrastructure electronic beacons for
identification communications and may also employ video automatic number plate recognition or vehicle magnetic
signature detection technologies at desired intervals to increase sustained monitoring of vehicles operating in critical
zones.

Inductive loop detection

Inductive loops can be placed in a roadbed to detect vehicles as they pass through the loop's magnetic field. The
simplest detectors simply count the number of vehicles during a unit of time (typically 60 seconds in the United
States) that pass over the loop, while more sophisticated sensors estimate the speed, length, and weight of vehicles
and the distance between them. Loops can be placed in a single lane or across multiple lanes, and they work with
very slow or stopped vehicles as well as vehicles moving at high-speed.

Video vehicle detection

Traffic flow measurement and automatic incident detection using video cameras is another form of vehicle detection.
Since video detection systems such as those used in automatic number plate recognition do not involve installing any
components directly into the road surface or roadbed, this type of system is known as a "non-intrusive" method of
traffic detection. Video from black-and-white or color cameras is fed into processors that analyze the changing
characteristics of the video image as vehicles pass. The cameras are typically mounted on poles or structures above
or adjacent to the roadway. Most video detection systems require some initial configuration to "teach" the
processor the baseline background image. This usually involves inputting known measurements such as the distance
between lane lines or the height of the camera above the roadway. A single video detection processor can detect
traffic simultaneously from one to eight cameras, depending on the brand and model. The typical output from a
video detection system is lane-by-lane vehicle speeds, counts, and lane occupancy readings. Some systems provide


additional outputs including gap, headway, stopped-vehicle detection, and wrong-way vehicle alarms.

Bluetooth Detection

Bluetooth is a new, precise and cost efficient way to measure travel time and make origin/destination analysis.
Bluetooth is a wireless standard used to communicate between electronic devices like mobile/smart phones,
headsets, navigation systems, computers etc. Bluetooth road sensors like BLIP Systems BlipTrack™ sensor,
detects the unique anonymous ID from Bluetooth devices in passing vehicles and calculates travel time and provides
data for origin/destination matrixes. Compared to other traffic measurement technologies, Bluetooth measurement
has some significant advantages:

Inexpensive per measurement point.
Inexpensive on physical installation compared to other technologies
No roadside maintenance needed
Quick and easy configuration and calibration of complete solution

And data from the system is as valid as data from any other traffic measurement technology.

Intelligent transport applications
Emergency vehicle notification systems

The in-vehicle eCall is an emergency call generated either manually by the vehicle occupants or automatically via
activation of in-vehicle sensors after an accident. When activated, the in-vehicle eCall device will establish an
emergency call carrying both voice and data directly to the nearest emergency point (normally the nearest E1-1-2
Public-safety answering point, PSAP). The voice call enables the vehicle occupant to communicate with the trained
eCall operator. At the same time, a minimum set of data will be sent to the eCall operator receiving the voice call.

The minimum set of data contains information about the incident, including time, precise location, the direction the
vehicle was traveling, and vehicle identification. The pan-European eCall aims to be operative for all new type-
approved vehicles as a standard option. Depending on the manufacturer of the eCall system, it could be mobile
phone based (Bluetooth connection to an in-vehicle interface), an integrated eCall device, or a functionality of a
broader system like navigation, Telematics device, or tolling device. eCall is expected to be offered, at earliest, by
the end of 2010, pending standardization by the European Telecommunications Standards Institute and commitment
from large EU member states such as France and the United Kingdom.

The EC funded project SafeTRIP[citation needed] is developing an open ITS system that will improve road safety
and provide a resilient communication through the use of S-band satellite communication. Such platform will allow
for greater coverage of the Emergency Call Service within the EU.

Automatic road enforcement

Main article: Traffic enforcement camera

A traffic enforcement camera system, consisting of a camera and a vehicle-monitoring device, is used to detect and
identify vehicles disobeying a speed limit or some other road legal requirement and automatically ticket offenders
based on the license plate number. Traffic tickets are sent by mail. Applications include:



Speed cameras that identify vehicles traveling over the legal speed
limit. Many such devices use radar to detect a vehicle's speed or
electromagnetic loops buried in each lane of the road.
Red light cameras that detect vehicles that cross a stop line or
designated stopping place while a red traffic light is showing.
Bus lane cameras that identify vehicles traveling in lanes reserved
for buses. In some jurisdictions, bus lanes can also be used by
taxis or vehicles engaged in car pooling.
Level crossing cameras that identify vehicles crossing railways at
grade illegally. Congestion pricing gantry at North
Double white line cameras that identify vehicles crossing these Bridge Road, Singapore.
lines.
High-occupancy vehicle lane cameras for that identify vehicles
violating HOV requirements.
Turn cameras at intersections where specific turns are prohibited
on red. This type of camera is mostly used in cities or heavy
populated areas.

Variable speed limits

Further information: Speed limit#Variable speed limits Automatic speed enforcement gantry
or "Lombada Eletrônica" with ground
Recently some jurisdictions have begun experimenting with variable sensors at Brasilia, D.F.
speed limits that change with road congestion and other factors. Typically
such speed limits only change to decline during poor conditions, rather
than being improved in good ones. One example is on Britain's M25 motorway,
which circumnavigates London. On the most heavily traveled 14-mile (23 km)
section (junction 10 to 16) of the M25 variable speed limits combined with
automated enforcement have been in force since 1995. Initial results indicated
savings in journey times, smoother-flowing traffic, and a fall in the number of
accidents, so the implementation was made permanent in 1997. Further trials on
the M25 have been thus far proved inconclusive.[3]

Collision avoidance systems

Japan has installed sensors on its highways to notify motorists that a car is stalled
ahead.[4]

Dynamic Traffic Light Sequence

Intelligent RFID traffic control has been developed for dynamic traffic light
sequence. It circumvents or avoids problems that usually arise with systems that Example variable speed limit
use image processing and beam interruption techniques. RFID technology with sign in the United States.
appropriate algorithm and database were applied to a multi vehicle, multi lane and
multi road junction area to provide an efficient time management scheme. A dynamic time schedule was worked out
for the passage of each column. The simulation has shown that, the dynamic sequence algorithm has the ability to



intelligently adjust itself even with the presence of some extreme cases. The real time operation of the system able to
emulate the judgment of a traffic police officer on duty, by considering the number of vehicles in each column and
the routing proprieties.[5]

Cooperative systems on the road
Communication cooperation on the road includes car-to-car, car-to-infrastructure, and vice versa. Data available
from vehicles are acquired and transmitted to a server for central fusion and processing. These data can be used to
detect events such as rain (wiper activity) and congestion (frequent braking activities). The server processes a
driving recommendation dedicated to a single or a specific group of drivers and transmits it wirelessly to vehicles.
The goal of cooperative systems is to use and plan communication and sensor infrastructure to increase road safety.
The definition of cooperative systems in road traffic is according to the European Commission:[6]

"Road operators, infrastructure, vehicles, their drivers and other road users will cooperate to deliver the most
efficient, safe, secure and comfortable journey. The vehicle-vehicle and vehicle-infrastructure co-operative
systems will contribute to these objectives beyond the improvements achievable with stand-alone systems."

ITS World Congress
ITS World Congress is an world-wide annual event to promote and showcase ITS technologies.

Intelligent Transportation Society of America (ITS America) (http://www.itsa.org/) is a national event to promote
and showcase ITS technologies.

United States
In the United States, each state has a Intelligent Transportation Systems (ITS) chapter that holds a yearly
conference to promote and showcase ITS technologies and ideas. Representatives from each DOT (state, cities,
towns, and counties) within the state attend this conference.

See also
Automated planning and scheduling
Calibrated software
Driverless car
Intelligent speed adaptation
Intelligent Transportation Systems Institute
Map database management
Neveda Department of Transpotation ITS CCTV Cameras Example (http://www.nevadadot.com/cameras/)
National Transportation Communications for Intelligent Transportation System Protocol
Repellor vehicle
SCATS
Telematics
Traffic estimation and prediction system
Traffic Message Channel



Traffic optimization
Vehicular communication systems
Vehicular Ad-Hoc Network
Freeway Traffic Management System or COMPASS
RESCU - similar system to COMPASS used by the City of Toronto

References
1. ^ Monahan, Torin. 2007. "War Rooms" of the Street: Surveillance Practices in Transportation Control Centers. The
Communication Review 10 (4): 367-389.
2. ^ Tarnoff, Philip John, Bullock, Darcy M, Young, Stanley E, et al. Continuing Evolution of Travel Time Data
Information Collection and Processing,Transportation Research Board Annual Meeting 2009 Paper #09-2030
TRB 88th Annual Meeting Compendium of Papers DVD
3. ^ (PDF) Report (HC 15, 2004-05): Tackling congestion by making better use of England's motorways and trunk
roads (Full Report) (http://www.nao.org.uk/publications/nao_reports/04-05/040515.pdf) , National Audit Office,
26 November 2004, http://www.nao.org.uk/publications/nao_reports/04-05/040515.pdf, retrieved 2009-09-17
4. ^ Trend in Road Accidents, Japan (http://www.nilim.go.jp/english/conference/asia2006/8-6.pdf)
5. ^ Dynamic Traffic Light Sequence, Science Publications
(http://thescipub.com/abstract/10.3844/jcssp.2008.517.524)
6. ^ 3rd eSafety Forum, 25 March 2004

External links
Intelligent transportation system
(http://www.dmoz.org/Science/Technology/Transportation/Intelligent_Systems//) at the Open Directory
Project
ITS Handbook available for free download online (http://road-network-operations.piarc.org/)
Railway Safety, Reliability and Security: Technologies and Systems Engineering (http://www.igi-
global.com/book/railway-safety-reliability-security/61619)

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Categories: Transport engineering Intelligent transportation systems

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Intelligent transportation system wikipedia, the free encyclopedia